Ionic conductivity of SrO-Ta 2 O 5 and SrO-La 2 O 3 -Ta 2 O 5 compounds

The conductivities of Sr2Ta2O7, Sr3TaO5.5, Sr2LaTaO6 and Sr3LaTa3O12, both doped and undoped, were measured by the ac complex impedance technique over a temperature range of approximately 400–800 °C. The conductivity of Sr2Zr2xTa2 – 2xO7 –x at 800 °C increased from 5.4 × 10–6 S cm–1 for the undoped compound to 3.0 × 10–4 S cm–1 at ×= 0.1, and the activation energy correspondingly decreased from 0.98 to 0.63 eV. Sr3TaO5.5 and Sr2LaTaO6 were …